Stereolithography 3D printing of ceramic cores for hollow aeroengine turbine blades

Abstract

Ceramic cores with complex double-walled hollow cavity structures are required for fabricating high-performance aeroengine turbine blades for fifth- and higher-generation fighter aircrafts. However, conventional approaches for ceramic core fabrication are unsuitable for producing such complex structures, which has hampered the innovation and application of hollow turbine blades. Herein, a high-performance stereolithography 3D printing (SLA-3DP) method is introduced based on digital light processing to fabricate complex ceramic cores with 60 vol.% solid loading. A ceramic suspension was prepared with excellent rheological and photopolymerization properties and the SLA-3DP processing parameters were optimized based on a systematic study of the microstructure, cracking, bending strength, shrinkage, and porosity of the sintered cores. Based on the systematic characterization of high-throughput samples, an evaluation and prediction system was established for the microstructure, properties, and defect analysis of SLA-3DP ceramic cores. Finally, double-walled ceramic cores and cast single-crystal hollow turbine blades were successfully prepared. The performance data and process parameters of SLA-3DP ceramic core obtained in this work could predict and guide the selection of the most effective process parameters.